[user5994461]

>>> All the "I can't say" responses will derail a lot of interviewers though.

Not so sure about that.

The majority of interviews in the HN bubbles is hours of technical questions and quizzes, where the interviewers will not ask a single question about your resume.

Outside of this bubble, the more mature interviewers, who did hundreds and hundreds of interviewers, are not moved by a "This is confidential... I could talk about -other thing- instead".